SubmissionNumber#=%=#62 FinalPaperTitle#=%=#Groningen team D at SemEval-2024 Task 8: Exploring data generation and a combined model for fine-tuning LLMs for Multidomain Machine-Generated Text Detection ShortPaperTitle#=%=# NumberOfPages#=%=#8 CopyrightSigned#=%=#Thijs Brekhof JobTitle#==#Student Organization#==#University of Groningen Abstract#==#In this system description, we describe our process and the systems that we created for the subtasks A monolingual, A multilingual, and B for the SemEval-2024 Task 8: Multigenerator, Multidomain, and Multilingual Black-Box MachineGenerated Text Detection. This shared task aims at detecting and differentiating between machinegenerated text and human-written text. Subtask A is focused on detecting if a text is machinegenerated or human-written both in a monolingual and a multilingual setting. Subtask B is also focused on detecting if a text is human-written or machine-generated, though it takes it one step further by also requiring the detection of the correct language model used for generating the text. For the monolingual aspects of this task, our approach is centered around fine-tuning a debertav3-large LM. For the multilingual setting, we created an ensemble model utilizing different monolingual models and a language identification tool to classify each text. We also experiment with the generation of extra training data. Our results show that the generation of extra data aids our models and leads to an increase in accuracy. Author{1}{Firstname}#=%=#Thijs Author{1}{Lastname}#=%=#Brekhof Author{1}{Username}#=%=#thijsbrekhof Author{1}{Email}#=%=#t.j.brekhof@student.rug.nl Author{1}{Affiliation}#=%=#RUG Author{2}{Firstname}#=%=#Xuanyi Author{2}{Lastname}#=%=#Liu Author{2}{Username}#=%=#xuanyiii Author{2}{Email}#=%=#liuxuanyi0908@gmail.com Author{2}{Affiliation}#=%=#University of Groningen Author{3}{Firstname}#=%=#Yuwen Author{3}{Lastname}#=%=#Zhou Author{3}{Username}#=%=#yuwenzhou Author{3}{Email}#=%=#y.zhou.74@student.rug.nl Author{3}{Affiliation}#=%=#+31 610847416 Author{4}{Firstname}#=%=#Joris Author{4}{Lastname}#=%=#Ruitenbeek Author{4}{Username}#=%=#ijoris Author{4}{Email}#=%=#ruitenbeekjoris@gmail.com Author{4}{Affiliation}#=%=#Rijksuniversiteit Groningen ========== èéáğö